Conor McGregor celebrated his historic triumph at UFC 205 in the best possible way after he confirmed that he and girlfriend Dee Devlin are expecting their first child in May next year, triggering speculation that the Irishman could end his mixed martial arts career.

McGregor delivered one of his most punishing performances in the early hours of Sunday morning when he knocked out Eddie Alvarez in the second round of their lightweight title fight, adding the 155-pound belt to the featherweight championship that he already held.

The fight represented McGregor’s third different weight category in four bouts, after beating Jose Aldo at UFC 193 at 145-pounds before his back-to-back meetings with Nate Diaz at UFC 196 and 202 at the welterweight limit of 170-pounds.

The 28-year-old teased a big announcement in the build-up to the fight, and after revelling in the glory of holding two UFC belts at the same time in front of a partisan Irish crowd, he confirmed that he and Devlin are expecting a baby next year.

“I'm going to be a daddy early next year. I'm crapping my jocks!” said McGregor in his post-fight press conference at Madison Square Garden in New York, where he momentarily forget the due date as he claimed their child will arrive in March before being informed it’s actually May.

"It's going to mess with my head. I just want to have this baby and take some time.”

However, McGregor went on to claim he needs a good offer to come back to the Octagon, and even claimed that part of that offer would be a share in the UFC brand due to his worth that has spiralled upwards over the last three years.

“I've got a family now, so I want ownership. I want an equal share,” McGregor added. “Whoever owns this company needs to come to me and give me a real slice. Bring me in on this for real. Make me an owner. I need to be set for life."